Systems and methods for control signaling for beam searching latency reduction

ABSTRACT

Systems and methods for control signaling for beam searching latency reduction are disclosed herein. A g Node B (gNB) may determine that a first Synchronization Signal Block (SSB) and a second SSB are to be spatially correlated and may select a first transmit (Tx) beam to transmit the first SSB and a second Tx beam to transmit the second SSB accordingly. The gNB may also transmit a correlation message including spatial correlation information to help a UE determine the spatial correlation. The UE may measure the first SSB on a first subset of a plurality of receive (Rx) beams and measure the second. SSB on a second subset of the plurality of Rx beams, and select an Rx beam for one or both. In some embodiments, channel state information reference signals (CSI-RS) that are quasi co-located (QCLed) with a Oven SSB may be measured in place of the SSB.

TECHNICAL FIELD

This application relates generally to wireless communication systems,and more specifically to control signaling for beam searching latencyreduction.

BACKGROUND

Wireless mobile communication technology uses various standards andprotocols to transmit data between a base station and a wireless mobiledevice. Wireless communication system standards and protocols caninclude the 3rd Generation Partnership Project (3GPP) long termevolution (LTE) (e.g., 4G) or new radio (NR) (e.g., 5G); the Instituteof Electrical and Electronics Engineers (IEEE) 802.16 standard, which iscommonly known to industry groups as worldwide interoperability formicrowave access (WiMAX); and the IEEE 802.11 standard for wirelesslocal area networks (WLAN), which is commonly known to industry groupsas Wi-Fi. In 3GPP radio access networks (RANs) in LTE systems, the basestation can include a RAN Node such as a Evolved Universal TerrestrialRadio Access Network (E-UTRAN) Node B (also commonly denoted as evolvedNode B, enhanced Node B, eNodeB, or eNB) and/or Radio Network Controller(RNC) in an E-UTRAN, which communicate with a wireless communicationdevice, known as user equipment (UE). In fifth generation (5G) wirelessRANs, RAN Nodes can include a 5G Node, NR node (also referred to as anext generation Node B or g Node B (gNB)).

RANs use a radio access technology (RAT) to communicate between the RANNode and UE. RANs can include global system for mobile communications(GSM), enhanced data rates for GSM evolution (EDGE) RAN (GERAN),Universal Terrestrial Radio Access Network (UTRAN), and/or E-UTRAN,which provide access to communication services through a core network.Each of the RANs operates according to a specific 3GPP RAT. For example,the GERAN implements GSM and/or EDGE RAT, the UTRAN implements universalmobile telecommunication system (UMTS) RAT or other 3 GPP RAT, theE-UTRAN implements LTE RAT, and NG-RAN implements 5G RAT. In certaindeployments, the E-UTRAN may also implement 5G RAT.

Frequency bands for 5G NR may be separated into two different frequencyranges. Frequency Range 1 (FR1) includes sub-6 GHz frequency bands, someof which are bands that may be used by previous standards, but maypotentially be extended to cover potential new spectrum offerings from410 MHz to 7125 MHz. Frequency Range 2 (FR2) includes frequency bandsfrom 24.25 GHz to 52.6 GHz. Bands in the millimeter wave (mmWave) rangeof FR2 have shorter range but higher available bandwidth than bands inthe FR1. Skilled persons will recognize these frequency ranges, whichare provided by way of example, may change from time to time or fromregion to region.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

To easily identify the discussion of any particular element or act, themost significant digit or digits in a reference number refer to thefigure number in which that element is first introduced.

FIG. 1 illustrates a timeline of a beam search performed for a pluralityof Synchronization Signal Blocks (SSBs) performed independently.

FIG. 2 illustrates a timeline of a beam search that leverages anunderstanding of spatial correlation of signals, according to anembodiment.

FIG. 3 includes a diagram of the result of a use by a UE of a number ofgroups of spatially correlated signals parameter provided by a gNB,according to an embodiment.

FIG. 4 includes a diagram of the result of a use by a UE of a number ofgroups of spatially correlated signals parameter provided by a gNB,according to an embodiment.

FIG. 5 illustrates a diagram illustrating possible SynchronizationSignal Block (SSB) and/or Channel State Information Reference Signal(CSI-RS) relationships, according to embodiments herein.

FIG. 6 illustrates a timeline of the use a plurality of Channel StateInformation Reference Signals (CSI-RSs), according to an embodiment.

FIG. 7 illustrates a timeline of the use of a plurality of Channel StateInformation Reference Signals (CSI-RSs) arranged according to FrequencyDivision Multiplexing (FDM), according to an embodiment.

FIG. 8 illustrates a system in accordance with one embodiment.

FIG. 9 illustrates a user equipment (UE) in accordance with oneembodiment.

FIG. 10 illustrates a network node in accordance with one embodiment.

FIG. 11 illustrates a device in accordance with one embodiment.

FIG. 12 illustrates example interfaces in accordance with oneembodiment.

FIG. 13 illustrates components in accordance with one embodiment.

DETAILED DESCRIPTION

To increase a link budget between a gNB and a UE, both the gNB and theUE may utilize analog beamforming for high frequency bands. A relativelygood gNB-UE beam pair can help to increase the coverage as opposed to alower quality gNB-UE beam pair.

In some systems, the UE measures Synchronization Signal Block (SSB) orChannel State Information Reference Signal (CSI-RS) resources withdifferent receive (Rx) beams in order to determine a good gNB-UE pairbetween a given SSB and/or CSI-RS and the given Rx beam. In somesystems, the gNB performs this task without first receiving anycorresponding information from the gNB. In these cases, the UE performsthe beam search for each SSB and/or CSI-RS independently.

FIG. 1 illustrates a timeline 100 of a beam search performed for aplurality of SSBs performed independently. First, the UE uses a first Rxbeam 102 to search for the SSB0 106. Then the UE uses the first Rx beam102 to search for an SSB1 108. Then the UE uses the first Rx beam 102 tosearch for an SSB2 110. Then the UE uses the first Rx beam 102 to searchfor the SSB3 112. The UE may continue using the first Rx beam 102 tosearch for as many SSBs as are being used in this manner.

Then the UE uses a second Rx beam 104 to search for the SSB0 106. Thenthe UE uses a second Rx beam 104 to search for the SSB1 108. Then the UEuses the second Rx beam 104 to search for the SSB2 110. Then the UE usesthe second Rx beam 104 to search for the SSB3 112. The UE may continueusing the second Rx beam 104 to search for as many SSBs are being usedin this manner.

The above process may continue for up to as many beams (e.g., beamsother than the first Rx beam 102 and second Rx beam 104) that the UE isconfigured to use/search on.

Systems as described in relation to FIG. 1 may be able to be improved(e.g., perform a beam search in less time, resulting in lower latencybeam searching) when information about a spatial correlation of two ormore searched-for signals is provided by the gNB to the UE (or isotherwise known at the UE).

Signals that are spatially correlated may be understood to be signalsthat are transmitted by a gNB such that a projected measurement (e.g., aReference Signal Receive Power (RSRP) measurement or aSignal-to-Interference Plus Noise Ratio (SINR) measurement) differenceof a reception at an Rx beam of the UE of a first correlated signal on afirst Tx beam and a reception at the same Rx beam of the UE of a secondcorrelated signal on a second Tx beam is less than a threshold. Forexample, an SSB transmitted on a first beam may be spatially correlatedwith a second SSB, a CSI-RS, or another signal that is transmitted on asecond beam if a change in a signal measurement (e.g., RSRP or SINR)between the two signals at the same Rx beam of the UE is not projectedto exceed a threshold. As another example, a CSI-RS transmitted on afirst beam may be spatially correlated with an SSB, a second CSI-RS, oranother signal that is transmitted on a second beam if a change in asignal measurement (e.g., RSRP or SINR) measurement between the twosignals at the same Rx beam of the UE is not projected to exceed athreshold. Spatial correlation may include, but is not limited to,signals that are quasi co-located (QCLed) with each other (e.g., QCLType-D). A gNB (or other entity) that is determining spatialcorrelations between signals and transmitting them accordingly may besaid to be transmitting signals according to a spatial correlationconfiguration.

For some signals that are spatially correlated, a UE can perform beamsearching jointly by leveraging its understanding about the spatialcorrelation of said signals. Among other cases, embodiments disclosedherein that describe this behavior may help to improve with beamsearching for secondary cell (SCell) activation, beam searching forhandover, beam searching for new beam identification from beam failure,beam searching for initial access, and/or beam searching for assistantTransmission Reception Point (TRP) discovery for multi-TRP operation.

FIG. 2 illustrates a timeline 200 of a beam search that leverages anunderstanding of spatial correlation of signals, according to anembodiment. In FIG. 2, a UE is aware that the SSB0 202 and the SSB1 204have a first spatial correlation 206. Further, the UE is aware that theSSB2 208 and the SSB3 210 have a second spatial correlation 212.

The UE then proceeds to use a first Rx beam 214 to search for the SSB0202. The UE then proceeds to search for the SSB1 204 using the second Rxbeam 216. Because the SSB0 202 and the SSB SSB1 204 have a first spatialcorrelation 206 (and this is known at the UE), it is inferred that asignal measurement of the SSB1 204 on the first Rx beam 214, had itactually been determined by the UE, would have changed relatively littlefrom the signal measurement of the SSB0 202 as already measured on thefirst Rx beam 214. Accordingly, the UE can estimate an Rx receive beammatch between the SSB1 204 and the first Rx beam 214 without actuallytaking the corresponding measurement directly. Further, based on thisknowledge of spatial correlation, it is further inferred that a signalmeasurement of the SSB0 202 on the second Rx beam 216, had it actuallybeen determined by the UE, would have changed relatively little from thesignal measurement of the SSB1 204 as already measured on the second Rxbeam 216. Accordingly, the UE can estimate a Rx receive beam matchbetween the SSB0 202 and the second Rx beam 216 without actually takingthe corresponding measurement directly.

The UE then proceeds to use the first Rx beam 214 to search for an SSB2208 and the second Rx beam 216 to search for an SSB3 210. Because of thesecond spatial correlation 212, the UE can infer Rx receive beam matchinformation about the first Rx beam 214 relative to the SSB3 210 andabout the second Rx beam 216 relative to the SSB2 208 in a mannersimilar that described in relation to SSB1 204 and SSB0 202 above.

The above process may then be repeated in relation to a third Rx beam218 and a fourth Rx beam 220.

At the end of the above process, the UE has Rx receive beam matchinformation (whether measured or estimated) for the first Rx beam 214,the second Rx beam 216, the third Rx beam 218, and the fourth Rx beam220 for each of the SSB0 202, the SSB1 204, the SSB2 208, and the SSB3210. Compared to the process in FIG. 1. (which spans over the sameamount of SSB transmissions), the UE has much more information. (In theexample of FIG. 1, the UE ends the process with Rx beam matchinformation for only the first Rx beam 102 and the second Rx beam 104relative to each of the SSB0 106, the SSB1 108, the SSB2 110, and theSSB3 112.)

The spatial correlation between signals (e.g., SSBs, CSI-RSs) may bealready known to the UE due to a pre-determined signal correlationpattern used by the gNB. Alternatively, the spatial correlation betweensignals may be known to the UE due to the application of apre-determined rule. For example, in some cases it may be that the UEassumes that all relevant signals (e.g., all SSBs and/or all CSI-RSs)transmitted in the same slot and/or subframe are spatially correlated.

In some embodiments, the gNB can provide the spatial correlationinformation for, for example, one or more SSBs and/or CSI-RSs to reduceUE beam searching latency. This spatial correlation information could beapplied as to SSBs and/or CSI-RSs within the same serving cell, and/orit may be applied to SSBs and/or CSI-RSs across a plurality of servingcells. In some embodiments, this signaling may come from higher layersignaling (e.g., System Information Block (SIB) signaling and/or RadioResource Control (RRC) messaging). In other embodiments, this signalingit may come from physical layer signaling (e.g., Master InformationBlock (MIB) signaling).

In some embodiments that use gNB signaling to provide spatialcorrelation information, the gNB may send a parameter indicating thenumber of groups of spatially correlated signals (N). The UE may receivethis parameter and may use it to determine the correlations betweenreceived SSBs

FIG. 3 includes a diagram 300 of the result of a use by a UE of a numberof groups of spatially correlated signals parameter provided by a gNB,according to an embodiment. In FIG. 3, there are 8 total SSBs and thegNB has indicated that there are 4 groupings of spatially correlatedSSBs (in other words, N=4). The UE then divides the total (8) by thenumber of groupings parameter (4) and determines that each spatiallycorrelated group has 2 SSBs. The UE therefore assumes that that everyconsecutive 2 SSBs are spatially correlated. Accordingly, the UE willtreat the first SSB 302 and the second SSB 304 as spatially correlated(group 1), the third SSB 306 and the fourth SSB 308 as spatiallycorrelated (group 2), the fifth SSB 310 and sixth SSB 312 as spatiallycorrelated (group 3), and the seventh SSB 314 and the eighth SSB 316 asspatially correlated (group 4). Note that the ordinals used in thediscussion of FIG. 3 (e.g., first, fifth) are given for explanatorypurposes, and are not intended to be mapped to an SSB identifier (e.g.,SSB1, SSB3) that may be used by the system.

FIG. 4 includes a diagram 400 of the result of a use by a UE of a numberof groups of spatially correlated signals parameter provided by a gNB,according to an embodiment. In FIG. 3, there are 8 total SSBs and thegNB has indicated that there are 4 groupings of spatially correlatedSSBs (in other words, N=4). The UE then assumes that for every k from 1. . . N, the SSBs in a group can be calculated using the pattern {SSB k,SSB N+k, SSB 2N+k, SSB 3N+k, . . . }, resulting in every kth SSB beingunderstood to be spatially correlated. This pattern is followed for asmany as multiples of N are needed to cover the entire SSB set.

In the example of FIG. 4, only {SSB k, SSB N+k} is needed, due to N=4and the total of 8 SSBs. Accordingly, the UE will treat the first SSB402 and the fifth SSB 410 as spatially correlated (group 1), the secondSSB 404 and the sixth SSB 412 as spatially correlated (group 2), thethird SSB 406 and the seventh SSB 414 as spatially correlated (group 3),and the fourth SSB 408 and the eighth SSB 416 as spatially correlated(group 4). Note that the ordinals used in the discussion of FIG. 4(e.g., first, fifth) are given for explanatory purposes, and notintended to be mapped to an SSB identifier (e.g., SSB1, SSB3) that maybe used by the system.

In some embodiments that use gNB signaling to provide spatialcorrelation information, the gNB may use signaling that communicates alist of SSBs that are spatially correlated. This list may include, forone or more given SSBs on the list, an identification of one or moreother SSBs to which the given SSB is spatially correlated.

In some embodiments that use gNB signaling to provide spatialcorrelation information, the gNB may use signaling that configuresgroupings of SSBs that are spatially correlated. Groupings so configuredmay be different than, e.g., the groupings discussed relative to FIG. 3and FIG. 4 above, at least in that in this case the gNB may configure adifferent (variable) amount of SSBs per group.

In some embodiments that use gNB signaling to provide spatialcorrelation information, the gNB may use signaling that indicates one ofa plurality of candidate patterns of correlated SSBs. These candidatecorrelation patterns may be known at the UE. The UE may then apply thecandidate correlation pattern corresponding to the received indicationin order to determine which SSBs are spatially correlated.

It is further contemplated that a CSI-RS associated to (sent on the samebeam as) one or more SSBs may be useful in methods disclosed herein.Accordingly, it may be useful to understand when a CSI-RS is quasico-located (QCLed) to an SSB and/or spatially correlated with anotherCSI-RS.

A spatial correlation of a CSI-RS could be determined based on the SSBwhich is configured as its source reference signal of QCL-typeD. In someembodiments, it may be that CSI-RS resources are considered spatiallycorrelated when they are configured with the same SSB as the sourcereference signal of QCL-typeD.

In other embodiments, it may be that CSI-RS resources are consideredspatially correlated based on the spatial correlations of the respectiveSSBs which are configured as the source reference signal of QCL-typeD.In this case, a CSI-RS may be considered spatially QCLed with SSBs thatare spatially correlated with the source SSB for QCL-typeD for theCSI-RS. Further, the CSI-RS may be considered spatially correlated withCSI-RS resources whose source QCL-typeD SSB is spatially correlated withits own source QCL-typeD SSB.

In cases where the QCL-typeD is not configured for a CSI-RS, the UEshall not assume the CSI-RS is spatially correlated with other CSI-RSsor SSBs. In alternative embodiments, the UE may expect the QCL-typeD forCSI-RS to be configured (when it is applicable).

FIG. 5 illustrates a diagram 500 illustrating possible SSB and/or CSI-RSrelationships, according to embodiments herein. The SSB0 502 may bespatially correlated with the SSB1 504, but not spatially correlatedwith the SSB2 506. The SSB0 502 may be QCLed (under QCL-typeD) with theCSI-RS0 508. The SSB1 504 may be QCLed (under QCL-typeD) with theCSI-RS1 510. The SSB2 506 may be QCLed (under QCL-typeD) with theCSI-RS2 512. Finally, because the SSB0 502 and the SSB1 504 arespatially correlated, it may be that their respective QCLed CSI-RSs, theCSI-RS0 508 and the CSI-RS1 510, are also considered to be spatiallycorrelated. Because neither of SSB0 502 nor SSB1 504 are spatiallycorrelated with SSB2 506, the CSI-RS2 512 that is QCLed with the SSB2506 is not considered spatially correlated with either of theirrespective CSI-RSs, the CSI-RS0 508 and the CSI-RS1 510.

Embodiments disclosed herein are also contemplated to be compatible withmulti-Transmission Reception Point (multi-TRP) enabled networks. Inthese embodiments, the gNB may provide one or more of the following setsof information to the UE (e.g., by higher layer signaling): an actuallytransmitted SSB pattern used by the assistant TRP, a transmission powerof one or more SSBs from the assistant TRP, a relative transmissionpower of one or more SSBs from the assistant TRP, and/or a physical cellID of the assistant TRP. One or more of these sets of information may besent in, e.g., a correlation message.

In some embodiments that use gNB signaling to provide spatialcorrelation information, the gNB may transmit to the UE spatialcorrelation information associated with the assistant TRP's SSB spatialcorrelation configuration. It may be that this information may be formedby the gNB and used by the UE (relative to the TRP SSBs) in any mannerdescribed herein.

In embodiments involving a neighbor TRP or cell search, it may be thatan SSB periodicity is relatively large. In these cases, the gNB mayconfigure one or more CSI-RSs to assist a UE in cell discovery in amanner that is quicker than using just the SSBs alone. In someembodiments, the one or more CSI-RSs have a much wider bandwidthcompared to an associated SSB, and therefore their use may result in amore accurate and faster search than using SSB alone (even apart fromconsidering the additional detection opportunities given relative to theuse case of SSBs alone). CSI-RSs may be configured as assistance signalsfor cell search and beam measurement relative to their correspondingSSBs. Accordingly, one or more CSI-RSs that are QCLed (e.g., Type-D)with their corresponding SSBs (e.g., in the manner described in FIG. 5above) may operate as a reference signal that is useful (e.g., togenerate Rx receive beam match information) relative to itscorresponding SSB. In some embodiments, these CSI-RSs may be, e.g.,aperiodic CSI-RSs (A-CSI-RSs).

FIG. 6 illustrates a timeline 600 of the use a plurality of CSI-RSs,according to an embodiment. A gNB may transmit a set of SSBs thatincludes an SSB1 602, and SSB2 604, an SSB3 606, and an SSB4 608 with aperiodicity 610 that is relatively large. To speed up the neighbor TRP,beam, or other search, the gNB may configure a CSI-RS for each of theSSBs 602-608. For example, the gNB may configure a CSI-RS1 612 that isQCLed (Type-D) with the SSB1 602, a CSI-RS2 614 that is QCLed (Type-D)with the SSB2 604, a CSI-RS3 616 that is QCLed (Type-D) with the SSB3606, and a CSI-RS4 618 that is QCLed (Type-D) with the SSB4 608. Theavailability of the CSI-RS1 612 to CSI-RS4 618 may allow the UE to takemeasurements on an Rx beam using a CSI-RS instead of its QCLed SSB,speeding up the process.

When the network has multiple panels and is capable of simultaneouslytransmitting multiple beams, then multiple CSI-RSs may be arrangedaccording to Frequency Division Multiplexing (FDM) to make the Tx beamsweep faster. In these embodiments, the UE can measure the widebandsignal, and the CSI-RS quality (e.g., RSRP or SINR) of multiple CSI-RSsat one time to obtain best Tx beam much faster. Further, the same CSI-RScan be repeated in time domain to further assist UE in Rx beam sweep. Insome embodiments, these CSI-RSs may be, e.g., A-CSI-RSs.

FIG. 7 illustrates a timeline 700 of the use of a plurality of CSI-RSsarranged according to FDM, according to an embodiment. A gNB maytransmit a set of SSBs that includes an SSB1 702, an SSB2 704, an SSB3706, and an SSB4 708 with a periodicity 710 that is relatively large. Tospeed up the neighbor TRP, beam, or other search, the gNB may configurea SCI-RS for each of the SSBs 702-708. For example, the gNB mayconfigure a CSI-RS1 712 that is QCLed (Type-D) with the SSB1 702, aCSI-RS2 714 that is QCLed (Type-D) with the SSB2 704, a CSI-RS3 716 thatis QCLed (Type-D) with the SSB3 706, and a CSI-RS4 718 that is QCLed(Type-D) with the SSB4 708. Further, as shown, each of the CSI-RSs712-718 may be arranged according to FDM so that more than one (in theillustrated case, all four) of them may be sent at the same time. Theuse of FDM may conserve time resources such that a sending of one ormore of the CSI-RSs 712-718 may be repeated at a different time (asillustrated). The availability of the CSI-RSs 712-718 may allow the UEto take measurements on an Rx beam using a CSI-RS instead of its QCLedSSB, speeding up the process.

FIG. 8 illustrates an example architecture of a system 800 of a network,in accordance with various embodiments. The following description isprovided for an example system 800 that operates in conjunction with theLTE system standards and 5G or NR system standards as provided by 3GPPtechnical specifications. However, the example embodiments are notlimited in this regard and the described embodiments may apply to othernetworks that benefit from the principles described herein, such asfuture 3GPP systems (e.g., Sixth Generation (6G)) systems, IEEE 802.16protocols (e.g., WMAN, WiMAX, etc.), or the like.

As shown by FIG. 8, the system 800 includes UE 802 and UE 804. In thisexample, the UE 802 and the UE 804 are illustrated as smartphones (e.g.,handheld touchscreen mobile computing devices connectable to one or morecellular networks), but may also comprise any mobile or non-mobilecomputing device, such as consumer electronics devices, cellular phones,smartphones, feature phones, tablet computers, wearable computerdevices, personal digital assistants (PDAs), pagers, wireless handsets,desktop computers, laptop computers, in-vehicle infotainment (IVI),in-car entertainment (ICE) devices, an Instrument Cluster (IC), head-updisplay (HUD) devices, onboard diagnostic (OBD) devices, dashtop mobileequipment (DME), mobile data terminals (MDTs), Electronic EngineManagement System (EEMS), electronic/engine control units (ECUs),electronic/engine control modules (ECMs), embedded systems,microcontrollers, control modules, engine management systems (EMS),networked or “smart” appliances, MTC devices, M2M, IoT devices, and/orthe like.

In some embodiments, the UE 802 and/or the UE 804 may be IoT UEs, whichmay comprise a network access layer designed for low power IoTapplications utilizing short-lived UE connections. An IoT UE can utilizetechnologies such as M2M or MTC for exchanging data with an MTC serveror device via a PLMN, ProSe or D2D communication, sensor networks, orIoT networks. The M2M or MTC exchange of data may be a machine-initiatedexchange of data. An IoT network describes interconnecting IoT UEs,which may include uniquely identifiable embedded computing devices(within the Internet infrastructure), with short-lived connections. TheIoT UEs may execute background applications (e.g., keep-alive messages,status updates, etc.) to facilitate the connections of the IoT network.

The UE 802 and UE 804 may be configured to connect, for example,communicatively couple, with an access node or radio access node (shownas (R)AN 816). In embodiments, the (R)AN 816 may be an NG RAN or a SGRAN, an E-UTRAN, or a legacy RAN, such as a UTRAN or GERAN. As usedherein, the term “NG RAN” or the like may refer to a (R)AN 816 thatoperates in an NR or SG system, and the term “E-UTRAN” or the like mayrefer to a (R)AN 816 that operates in an LTE or 4G system. The UE 802and UE 804 utilize connections (or channels) (shown as connection 806and connection 808, respectively), each of which comprises a physicalcommunications interface or layer (discussed in further detail below).

In this example, the connection 806 and connection 808 are airinterfaces to enable communicative coupling, and can be consistent withcellular communications protocols, such as a GSM protocol, a CDMAnetwork protocol, a PTT protocol, a POC protocol, a UMTS protocol, a3GPP LTE protocol, a SG protocol, a NR protocol, and/or any of the othercommunications protocols discussed herein. In embodiments, the UE 802and UE 804 may directly exchange communication data via a ProSeinterface 810. The ProSe interface 810 may alternatively be referred toas a sidelink (SL) interface 110 and may comprise one or more logicalchannels, including but not limited to a PSCCH, a PSSCH, a PSDCH, and aPSBCH.

The UE 804 is shown to be configured to access an AP 812 (also referredto as “WLAN node,” “WLAN,” “WLAN Termination,” “WT” or the like) viaconnection 814. The connection 814 can comprise a local wirelessconnection, such as a connection consistent with any IEEE 802.11protocol, wherein the AP 812 would comprise a wireless fidelity (Wi-Fi®)router. In this example, the AP 812 may be connected to the Internetwithout connecting to the core network of the wireless system (describedin further detail below). In various embodiments, the UE 804, (R)AN 816,and AP 812 may be configured to utilize LWA operation and/or LWIPoperation. The LWA operation may involve the UE 804 in RRC_CONNECTEDbeing configured by the RAN node 818 or the RAN node 820 to utilizeradio resources of LTE and WLAN. LWIP operation may involve the UE 804using WLAN radio resources (e.g., connection 814) via IPsec protocoltunneling to authenticate and encrypt packets (e.g., IP packets) sentover the connection 814. IPsec tunneling may include encapsulating theentirety of original IP packets and adding a new packet header, therebyprotecting the original header of the IP packets.

The (R)AN 816 can include one or more AN nodes, such as RAN node 818 andRAN node 820, that enable the connection 806 and connection 808. As usedherein, the terms “access node,” “access point,” or the like maydescribe equipment that provides the radio baseband functions for dataand/or voice connectivity between a network and one or more users. Theseaccess nodes can be referred to as BS, gNBs, RAN nodes, eNBs, NodeBs,RSUs TRxPs or TRPs, and so forth, and can comprise ground stations(e.g., terrestrial access points) or satellite stations providingcoverage within a geographic area (e.g., a cell). As used herein, theterm “NG RAN node” or the like may refer to a RAN node that operates inan NR or SG system (for example, a gNB), and the term “E-UTRAN node” orthe like may refer to a RAN node that operates in an LTE or 4G system800 (e.g., an eNB). According to various embodiments, the RAN node 818or RAN node 820 may be implemented as one or more of a dedicatedphysical device such as a macrocell base station, and/or a low power(LP) base station for providing femtocells, picocells or other likecells having smaller coverage areas, smaller user capacity, or higherbandwidth compared to macrocells.

In some embodiments, all or parts of the RAN node 818 or RAN node 820may be implemented as one or more software entities running on servercomputers as part of a virtual network, which may be referred to as aCRAN and/or a virtual baseband unit pool (vBBUP). In these embodiments,the CRAN or vBBUP may implement a RAN function split, such as a PDCPsplit wherein RRC and PDCP layers are operated by the CRAN/vBBUP andother L2 protocol entities are operated by individual RAN nodes (e.g.,RAN node 818 or RAN node 820); a MAC/PHY split wherein RRC, PDCP, RLC,and MAC layers are operated by the CRAN/vBBUP and the PHY layer isoperated by individual RAN nodes (e.g., RAN node 818 or RAN node 820);or a “lower PHY” split wherein RRC, PDCP, RLC, MAC layers and upperportions of the PHY layer are operated by the CRAN/vBBUP and lowerportions of the PHY layer are operated by individual RAN nodes. Thisvirtualized framework allows the freed-up processor cores of the RANnode 818 or RAN node 820 to perform other virtualized applications. Insome implementations, an individual RAN node may represent individualgNB-DUs that are connected to a gNB-CU via individual F1 interfaces (notshown by FIG. 8). In these implementations, the gNB-DUs may include oneor more remote radio heads or RFEMs, and the gNB-CU may be operated by aserver that is located in the (R)AN 816 (not shown) or by a server poolin a similar manner as the CRAN/vBBUP. Additionally, or alternatively,one or more of the RAN node 818 or RAN node 820 may be next generationeNBs (ng-eNBs), which are RAN nodes that provide E-UTRA user plane andcontrol plane protocol terminations toward the UE 802 and UE 804, andare connected to an SGC via an NG interface (discussed infra). In V2Xscenarios one or more of the RAN node 818 or RAN node 820 may be or actas RSUs.

The term “Road Side Unit” or “RSU” may refer to any transportationinfrastructure entity used for V2X communications. An RSU may beimplemented in or by a suitable RAN node or a stationary (or relativelystationary) UE, where an RSU implemented in or by a UE may be referredto as a “UE-type RSU,” an RSU implemented in or by an eNB may bereferred to as an “eNB-type RSU,” an RSU implemented in or by a gNB maybe referred to as a “gNB-type RSU,” and the like. In one example, an RSUis a computing device coupled with radio frequency circuitry located ona roadside that provides connectivity support to passing vehicle UEs(vUEs). The RSU may also include internal data storage circuitry tostore intersection map geometry, traffic statistics, media, as well asapplications/software to sense and control ongoing vehicular andpedestrian traffic. The RSU may operate on the 5.9 GHz Direct ShortRange Communications (DSRC) band to provide very low latencycommunications required for high speed events, such as crash avoidance,traffic warnings, and the like. Additionally, or alternatively, the RSUmay operate on the cellular V2X band to provide the aforementioned lowlatency communications, as well as other cellular communicationsservices. Additionally, or alternatively, the RSU may operate as a Wi-Fihotspot (2.4 GHz band) and/or provide connectivity to one or morecellular networks to provide uplink and downlink communication. Thecomputing device(s) and some or all of the radio frequency circuitry ofthe RSU may be packaged in a weatherproof enclosure suitable for outdoorinstallation, and may include a network interface controller to providea wired connection (e.g., Ethernet) to a traffic signal controllerand/or a backhaul network.

The RAN node 818 and/or the RAN node 820 can terminate the air interfaceprotocol and can be the first point of contact for the UE 802 and UE804. In some embodiments, the RAN node 818 and/or the RAN node 820 canfulfill various logical functions for the (R)AN 816 including, but notlimited to, radio network controller (RNC) functions such as radiobearer management, uplink and downlink dynamic radio resource managementand data packet scheduling, and mobility management.

In embodiments, the UE 802 and UE 804 can be configured to communicateusing OFDM communication signals with each other or with the RAN node818 and/or the RAN node 820 over a multicarrier communication channel inaccordance with various communication techniques, such as, but notlimited to, an OFDMA communication technique (e.g., for downlinkcommunications) or a SC-FDMA communication technique (e.g., for uplinkand ProSe or sidelink communications), although the scope of theembodiments is not limited in this respect. The OFDM signals cancomprise a plurality of orthogonal subcarriers.

In some embodiments, a downlink resource grid can be used for downlinktransmissions from the RAN node 818 and/or the RAN node 820 to the UE802 and UE 804, while uplink transmissions can utilize similartechniques. The grid can be a time-frequency grid, called a resourcegrid or time-frequency resource grid, which is the physical resource inthe downlink in each slot. Such a time-frequency plane representation isa common practice for OFDM systems, which makes it intuitive for radioresource allocation. Each column and each row of the resource gridcorresponds to one OFDM symbol and one OFDM subcarrier, respectively.The duration of the resource grid in the time domain corresponds to oneslot in a radio frame. The smallest time-frequency unit in a resourcegrid is denoted as a resource element. Each resource grid comprises anumber of resource blocks, which describe the mapping of certainphysical channels to resource elements. Each resource block comprises acollection of resource elements; in the frequency domain, this mayrepresent the smallest quantity of resources that currently can beallocated. There are several different physical downlink channels thatare conveyed using such resource blocks.

According to various embodiments, the UE 802 and UE 804 and the RAN node818 and/or the RAN node 820 communicate data (for example, transmit andreceive) over a licensed medium (also referred to as the “licensedspectrum” and/or the “licensed band”) and an unlicensed shared medium(also referred to as the “unlicensed spectrum” and/or the “unlicensedband”). The licensed spectrum may include channels that operate in thefrequency range of approximately 400 MHz to approximately 3.8 GHz,whereas the unlicensed spectrum may include the 5 GHz band.

To operate in the unlicensed spectrum, the UE 802 and UE 804 and the RANnode 818 or RAN node 820 may operate using LAA, eLAA, and/or feLAAmechanisms. In these implementations, the UE 802 and UE 804 and the RANnode 818 or RAN node 820 may perform one or more known medium-sensingoperations and/or carrier-sensing operations in order to determinewhether one or more channels in the unlicensed spectrum is unavailableor otherwise occupied prior to transmitting in the unlicensed spectrum.The medium/carrier sensing operations may be performed according to alisten-before-talk (LBT) protocol.

LBT is a mechanism whereby equipment (for example, UE 802 and UE 804,RAN node 818 or RAN node 820, etc.) senses a medium (for example, achannel or carrier frequency) and transmits when the medium is sensed tobe idle (or when a specific channel in the medium is sensed to beunoccupied). The medium sensing operation may include CCA, whichutilizes at least ED to determine the presence or absence of othersignals on a channel in order to determine if a channel is occupied orclear. This LBT mechanism allows cellular/LAA networks to coexist withincumbent systems in the unlicensed spectrum and with other LAAnetworks. ED may include sensing RF energy across an intendedtransmission band for a period of time and comparing the sensed RFenergy to a predefined or configured threshold.

Typically, the incumbent systems in the 5 GHz band are WLANs based onIEEE 802.11 technologies. WLAN employs a contention-based channel accessmechanism, called CSMA/CA Here, when a WLAN node (e.g., a mobile station(MS) such as UE 802, AP 812, or the like) intends to transmit, the WLANnode may first perform CCA before transmission. Additionally, a backoffmechanism is used to avoid collisions in situations where more than oneWLAN node senses the channel as idle and transmits at the same time. Thebackoff mechanism may be a counter that is drawn randomly within theCWS, which is increased exponentially upon the occurrence of collisionand reset to a minimum value when the transmission succeeds.

The LBT mechanism designed for LAA is somewhat similar to the CSMA/CA ofWLAN. In some implementations, the LBT procedure for DL or ULtransmission bursts including PDSCH or PUSCH transmissions,respectively, may have an LAA contention window that is variable inlength between X and Y ECCA slots, where X and Y are minimum and maximumvalues for the CWSs for LAA. In one example, the minimum CWS for an LAAtransmission may be 9 microseconds (μs); however, the size of the CWSand a MCOT (for example, a transmission burst) may be based ongovernmental regulatory requirements.

The LAA mechanisms are built upon CA technologies of LTE-Advancedsystems. In CA, each aggregated carrier is referred to as a CC. A CC mayhave a bandwidth of 1.4, 3, 5, 10, 15 or 20 MHz and a maximum of fiveCCs can be aggregated, and therefore, a maximum aggregated bandwidth is100 MHz. In FDD systems, the number of aggregated carriers can bedifferent for DL and UL, where the number of UL CCs is equal to or lowerthan the number of DL component carriers. In some cases, individual CCscan have a different bandwidth than other CCs. In TDD systems, thenumber of CCs as well as the bandwidths of each CC is usually the samefor DL and UL.

CA also comprises individual serving cells to provide individual CCs.The coverage of the serving cells may differ, for example, because CCson different frequency bands will experience different pathloss. Aprimary service cell or PCell may provide a PCC for both UL and DL, andmay handle RRC and NAS related activities. The other serving cells arereferred to as SCells, and each SCell may provide an individual SCC forboth UL and DL. The SCCs may be added and removed as required, whilechanging the PCC may require the UE 802 to undergo a handover. In LAA,eLAA, and feLAA, some or all of the SCells may operate in the unlicensedspectrum (referred to as “LAA SCells”), and the LAA SCells are assistedby a PCell operating in the licensed spectrum. When a UE is configuredwith more than one LAA SCell, the UE may receive UL grants on theconfigured LAA SCells indicating different PUSCH starting positionswithin a same subframe.

The PDSCH carries user data and higher-layer signaling to the UE 802 andUE 804. The PDCCH carries information about the transport format andresource allocations related to the PDSCH channel, among other things.It may also inform the UE 802 and UE 804 about the transport format,resource allocation, and HARQ information related to the uplink sharedchannel. Typically, downlink scheduling (assigning control and sharedchannel resource blocks to the UE 804 within a cell) may be performed atany of the RAN node 818 or RAN node 820 based on channel qualityinformation fed back from any of the UE 802 and UE 804. The downlinkresource assignment information may be sent on the PDCCH used for (e.g.,assigned to) each of the UE 802 and UE 804.

The PDCCH uses CCEs to convey the control information. Before beingmapped to resource elements, the PDCCH complex-valued symbols may firstbe organized into quadruplets, which may then be permuted using asub-block interleaver for rate matching. Each PDCCH may be transmittedusing one or more of these CCEs, where each CCE may correspond to ninesets of four physical resource elements known as REGs. Four QuadraturePhase Shift Keying (QPSK) symbols may be mapped to each REG. The PDCCHcan be transmitted using one or more CCEs, depending on the size of theDCI and the channel condition. There can be four or more different PDCCHformats defined in LTE with different numbers of CCEs (e.g., aggregationlevel, L=1, 2, 4, or 8).

Some embodiments may use concepts for resource allocation for controlchannel information that are an extension of the above-describedconcepts. For example, some embodiments may utilize an EPDCCH that usesPDSCH resources for control information transmission. The EPDCCH may betransmitted using one or more ECCEs. Similar to above, each ECCE maycorrespond to nine sets of four physical resource elements known as anEREGs. An ECCE may have other numbers of EREGs in some situations.

The RAN node 818 or RAN node 820 may be configured to communicate withone another via interface 822. In embodiments where the system 800 is anLTE system (e.g., when CN 830 is an EPC), the interface 822 may be an X2interface. The X2 interface may be defined between two or more RAN nodes(e.g., two or more eNBs and the like) that connect to an EPC, and/orbetween two eNBs connecting to the EPC. In some implementations, the X2interface may include an X2 user plane interface (X2-U) and an X2control plane interface (X2-C). The X2-U may provide flow controlmechanisms for user data packets transferred over the X2 interface, andmay be used to communicate information about the delivery of user databetween eNBs. For example, the X2-U may provide specific sequence numberinformation for user data transferred from a MeNB to an SeNB;information about successful in sequence delivery of PDCP PDUs to a UE802 from an SeNB for user data; information of PDCP PDUs that were notdelivered to a UE 802; information about a current minimum desiredbuffer size at the Se NB for transmitting to the UE user data; and thelike. The X2-C may provide intra-LTE access mobility functionality,including context transfers from source to target eNBs, user planetransport control, etc.; load management functionality; as well asinter-cell interference coordination functionality.

In embodiments where the system 800 is a SG or NR system (e.g., when CN830 is an SGC), the interface 822 may be an Xn interface. The Xninterface is defined between two or more RAN nodes (e.g., two or moregNBs and the like) that connect to SGC, between a RAN node 818 (e.g., agNB) connecting to SGC and an eNB, and/or between two eNBs connecting to5GC (e.g., CN 830). In some implementations, the Xn interface mayinclude an Xn user plane (Xn-U) interface and an Xn control plane (Xn-C)interface. The Xn-U may provide non-guaranteed delivery of user planePDUs and support/provide data forwarding and flow control functionality.The Xn-C may provide management and error handling functionality,functionality to manage the Xn-C interface; mobility support for UE 802in a connected mode (e.g., CM-CONNECTED) including functionality tomanage the UE mobility for connected mode between one or more RAN node818 or RAN node 820. The mobility support may include context transferfrom an old (source) serving RAN node 818 to new (target) serving RANnode 820; and control of user plane tunnels between old (source) servingRAN node 818 to new (target) serving RAN node 820. A protocol stack ofthe Xn-U may include a transport network layer built on InternetProtocol (IP) transport layer, and a GTP-U layer on top of a UDP and/orIP layer(s) to carry user plane PDUs. The Xn-C protocol stack mayinclude an application layer signaling protocol (referred to as XnApplication Protocol (Xn-AP)) and a transport network layer that isbuilt on SCTP. The SCTP may be on top of an IP layer, and may providethe guaranteed delivery of application layer messages. In the transportIP layer, point-to-point transmission is used to deliver the signalingPDUs. In other implementations, the Xn-U protocol stack and/or the Xn-Cprotocol stack may be same or similar to the user plane and/or controlplane protocol stack(s) shown and described herein.

The (R)AN 816 is shown to be communicatively coupled to a corenetwork-in this embodiment, CN 830. The CN 830 may comprise one or morenetwork elements 832, which are configured to offer various data andtelecommunications services to customers/subscribers (e.g., users of UE802 and UE 804) who are connected to the CN 830 via the (R)AN 816. Thecomponents of the CN 830 may be implemented in one physical node orseparate physical nodes including components to read and executeinstructions from a machine-readable or computer-readable medium (e.g.,a non-transitory machine-readable storage medium). In some embodiments,NFV may be utilized to virtualize any or all of the above-describednetwork node functions via executable instructions stored in one or morecomputer-readable storage mediums (described in further detail below). Alogical instantiation of the CN 830 may be referred to as a networkslice, and a logical instantiation of a portion of the CN 830 may bereferred to as a network sub-slice. NFV architectures andinfrastructures may be used to virtualize one or more network functions,alternatively performed by proprietary hardware, onto physical resourcescomprising a combination of industry-standard server hardware, storagehardware, or switches. In other words, NFV systems can be used toexecute virtual or reconfigurable implementations of one or more EPCcomponents/functions.

Generally, an application server 834 may be an element offeringapplications that use IP bearer resources with the core network (e.g.,UMTS PS domain, LTE PS data services, etc.). The application server 834can also be configured to support one or more communication services(e.g., VoIP sessions, PTT sessions, group communication sessions, socialnetworking services, etc.) for the UE 802 and UE 804 via the EPC. Theapplication server 834 may communicate with the CN 830 through an IPcommunications interface 836.

In embodiments, the CN 830 may be an SGC, and the (R)AN 116 may beconnected with the CN 830 via an NG interface 824. In embodiments, theNG interface 824 may be split into two parts, an NG user plane (NG-U)interface 826, which carries traffic data between the RAN node 818 orRAN node 820 and a UPF, and the S1 control plane (NG-C) interface 828,which is a signaling interface between the RAN node 818 or RAN node 820and AMFs.

In embodiments, the CN 830 may be a SG CN, while in other embodiments,the CN 830 may be an EPC). Where CN 830 is an EPC, the (R)AN 116 may beconnected with the CN 830 via an S1 interface 824. In embodiments, theS1 interface 824 may be split into two parts, an S1 user plane (S1-U)interface 826, which carries traffic data between the RAN node 818 orRAN node 820 and the S-GW, and the S1-MME interface 828, which is asignaling interface between the RAN node 818 or RAN node 820 and MMEs.

FIG. 9 is a block diagram of an example UE 900 configurable according tovarious embodiments of the present disclosure, including by execution ofinstructions on a computer-readable medium that correspond to any of theexample methods and/or procedures described herein. The UE 900 comprisesone or more processor 902, transceiver 904, memory 906, user interface908, and control interface 910.

The one or more processor 902 may include, for example, an applicationprocessor, an audio digital signal processor, a central processing unit,and/or one or more baseband processors. Each of the one or moreprocessor 902 may include internal memory and/or may includeinterface(s) to communication with external memory (including the memory906). The internal or external memory can store software code, programs,and/or instructions for execution by the one or more processor 902 toconfigure and/or facilitate the UE 900 to perform various operations,including operations described herein. For example, execution of theinstructions can configure the UE 900 to communicate using one or morewired or wireless communication protocols, including one or morewireless communication protocols standardized by 3GPP such as thosecommonly known as 5G/NR, LTE, LTE-A, UMTS, HSPA, GSM, GPRS, EDGE, etc.,or any other current or future protocols that can be utilized inconjunction with the one or more transceiver 904, user interface 908,and/or control interface 910. As another example, the one or moreprocessor 902 may execute program code stored in the memory 906 or othermemory that corresponds to MAC, RLC, PDCP, and RRC layer protocolsstandardized by 3GPP (e.g., for NR and/or LTE). As a further example,the processor 902 may execute program code stored in the memory 906 orother memory that, together with the one or more transceiver 904,implements corresponding PHY layer protocols, such as OrthogonalFrequency Division Multiplexing (OFDM), Orthogonal Frequency DivisionMultiple Access (OFDMA), and Single-Carrier Frequency Division MultipleAccess (SC-FDMA).

The memory 906 may comprise memory area for the one or more processor902 to store variables used in protocols, configuration, control, andother functions of the UE 900, including operations corresponding to, orcomprising, any of the example methods and/or procedures describedherein. Moreover, the memory 906 may comprise non-volatile memory (e.g.,flash memory), volatile memory (e.g., static or dynamic RAM), or acombination thereof. Furthermore, the memory 906 may interface with amemory slot by which removable memory cards in one or more formats(e.g., SD Card, Memory Stick, Compact Flash, etc.) can be inserted andremoved.

The one or more transceiver 904 may include radio-frequency transmitterand/or receiver circuitry that facilitates the UE 900 to communicatewith other equipment supporting like wireless communication standardsand/or protocols. For example, the one or more transceiver 904 mayinclude switches, mixer circuitry, amplifier circuitry, filtercircuitry, and synthesizer circuitry. Such RF circuitry may include areceive signal path with circuitry to down-convert RF signals receivedfrom a front-end module (FEM) and provide baseband signals to a basebandprocessor of the one or more processor 902. The RF circuitry may alsoinclude a transmit signal path which may include circuitry to up-convertbaseband signals provided by a baseband processor and provide RF outputsignals to the FEM for transmission. The FEM may include a receivesignal path that may include circuitry configured to operate on RFsignals received from one or more antennas, amplify the received signalsand provide the amplified versions of the received signals to the RFcircuitry for further processing. The FEM may also include a transmitsignal path that may include circuitry configured to amplify signals fortransmission provided by the RF circuitry for transmission by one ormore antennas. In various embodiments, the amplification through thetransmit or receive signal paths may be done solely in the RF circuitry,solely in the FEM, or in both the RF circuitry and the FEM circuitry. Insome embodiments, the FEM circuitry may include a TX/RX switch to switchbetween transmit mode and receive mode operation.

In some exemplary embodiments, the one or more transceiver 904 includesa transmitter and a receiver that enable device 1200 to communicate withvarious 5G/NR networks according to various protocols and/or methodsproposed for standardization by 3 GPP and/or other standards bodies. Forexample, such functionality can operate cooperatively with the one ormore processor 902 to implement a PHY layer based on OFDM, OFDMA, and/orSC-FDMA technologies, such as described herein with respect to otherfigures.

The user interface 908 may take various forms depending on particularembodiments, or can be absent from the UE 900. In some embodiments, theuser interface 908 includes a microphone, a loudspeaker, slidablebuttons, depressible buttons, a display, a touchscreen display, amechanical or virtual keypad, a mechanical or virtual keyboard, and/orany other user-interface features commonly found on mobile phones. Inother embodiments, the UE 900 may comprise a tablet computing deviceincluding a larger touchscreen display. In such embodiments, one or moreof the mechanical features of the user interface 908 may be replaced bycomparable or functionally equivalent virtual user interface features(e.g., virtual keypad, virtual buttons, etc.) implemented using thetouchscreen display, as familiar to persons of ordinary skill in theart. In other embodiments, the UE 900 may be a digital computing device,such as a laptop computer, desktop computer, workstation, etc. thatcomprises a mechanical keyboard that can be integrated, detached, ordetachable depending on the particular exemplary embodiment. Such adigital computing device can also comprise a touch screen display. Manyexample embodiments of the UE 900 having a touch screen display arecapable of receiving user inputs, such as inputs related to exemplarymethods and/or procedures described herein or otherwise known to personsof ordinary skill in the art.

In some exemplary embodiments of the present disclosure, the UE 900 mayinclude an orientation sensor, which can be used in various ways byfeatures and functions of the UE 900. For example, the UE 900 can useoutputs of the orientation sensor to determine when a user has changedthe physical orientation of the UE 900's touch screen display. Anindication signal from the orientation sensor can be available to anyapplication program executing on the UE 900, such that an applicationprogram can change the orientation of a screen display (e.g., fromportrait to landscape) automatically when the indication signalindicates an approximate 90-degree change in physical orientation of thedevice. In this manner, the application program can maintain the screendisplay in a manner that is readable by the user, regardless of thephysical orientation of the device. In addition, the output of theorientation sensor can be used in conjunction with various exemplaryembodiments of the present disclosure.

The control interface 910 may take various forms depending on particularembodiments. For example, the control interface 910 may include anRS-232 interface, an RS-485 interface, a USB interface, an HDMIinterface, a Bluetooth interface, an IEEE (“Firewire”) interface, an I²Cinterface, a PCMCIA interface, or the like. In some exemplaryembodiments of the present disclosure, control interface 1260 cancomprise an IEEE 802.3 Ethernet interface such as described above. Insome embodiments of the present disclosure, the control interface 910may include analog interface circuitry including, for example, one ormore digital-to-analog (D/A) and/or analog-to-digital (A/D) converters.

Persons of ordinary skill in the art can recognize the above list offeatures, interfaces, and radio-frequency communication standards ismerely exemplary, and not limiting to the scope of the presentdisclosure. In other words, the UE 900 may include more functionalitythan is shown in FIG. 9 including, for example, a video and/orstill-image camera, microphone, media player and/or recorder, etc.Moreover, the one or more transceiver 904 may include circuitry forcommunication using additional radio-frequency communication standardsincluding Bluetooth, GPS, and/or others. Moreover, the one or moreprocessor 902 may execute software code stored in the memory 906 tocontrol such additional functionality. For example, directional velocityand/or position estimates output from a GPS receiver can be available toany application program executing on the UE 900, including variousexemplary methods and/or computer-readable media according to variousexemplary embodiments of the present disclosure.

FIG. 10 is a block diagram of an example network node 1000 configurableaccording to various embodiments of the present disclosure, including byexecution of instructions on a computer-readable medium that correspondto any of the example methods and/or procedures described herein.

The network node 1000 includes a one or more processor 1002, a radionetwork interface 1004, a memory 1006, a core network interface 1008,and other interfaces 1010. The network node 1000 may comprise, forexample, a base station, eNB, gNB, access node, or component thereof.

The one or more processor 1002 may include any type of processor orprocessing circuitry and may be configured to perform an of the methodsor procedures disclosed herein. The memory 1006 may store software code,programs, and/or instructions executed by the one or more processor 1002to configure the network node 1000 to perform various operations,including operations described herein. For example, execution of suchstored instructions can configure the network node 1000 to communicatewith one or more other devices using protocols according to variousembodiments of the present disclosure, including one or more methodsand/or procedures discussed above. Furthermore, execution of such storedinstructions can also configure and/or facilitate the network node 1000to communicate with one or more other devices using other protocols orprotocol layers, such as one or more of the PHY, MAC, RLC, PDCP, and RRClayer protocols standardized by 3GPP for LTE, LTE-A, and/or NR, or anyother higher-layer protocols utilized in conjunction with the radionetwork interface 1004 and the core network interface 1008. By way ofexample and without limitation, the core network interface 1008 comprisean S1 interface and the radio network interface 1004 may comprise a Uuinterface, as standardized by 3GPP. The memory 1006 may also storevariables used in protocols, configuration, control, and other functionsof the network node 1000. As such, the memory 1006 may comprisenon-volatile memory (e.g., flash memory, hard disk, etc.), volatilememory (e.g., static or dynamic RAM), network-based (e.g., “cloud”)storage, or a combination thereof.

The radio network interface 1004 may include transmitters, receivers,signal processors, ASICs, antennas, beamforming units, and othercircuitry that enables network node 1000 to communicate with otherequipment such as, in some embodiments, a plurality of compatible userequipment (UE). In some embodiments, the network node 1000 may includevarious protocols or protocol layers, such as the PHY, MAC, RLC, PDCP,and RRC layer protocols standardized by 3GPP for LTE, LTE-A, and/or5G/NR. According to further embodiments of the present disclosure, theradio network interface 1004 may include a PHY layer based on OFDM,OFDMA, and/or SC-FDMA technologies. In some embodiments, thefunctionality of such a PHY layer can be provided cooperatively by theradio network interface 1004 and the one or more processor 1002.

The core network interface 1008 may include transmitters, receivers, andother circuitry that enables the network node 1000 to communicate withother equipment in a core network such as, in some embodiments,circuit-switched (CS) and/or packet-switched Core (PS) networks. In someembodiments, the core network interface 1008 may include the S1interface standardized by 3GPP. In some embodiments, the core networkinterface 1008 may include one or more interfaces to one or more SGWs,MMES, SGSNs, GGSNs, and other physical devices that comprisefunctionality found in GERAN, UTRAN, E-UTRAN, and CDMA2000 core networksthat are known to persons of ordinary skill in the art. In someembodiments, these one or more interfaces may be multiplexed together ona single physical interface. In some embodiments, lower layers of thecore network interface 1008 may include one or more of asynchronoustransfer mode (ATM), Internet Protocol (IP)-over-Ethernet, SDH overoptical fiber, T1/E1/PDH over a copper wire, microwave radio, or otherwired or wireless transmission technologies known to those of ordinaryskill in the art.

The other interfaces 1010 may include transmitters, receivers, and othercircuitry that enables the network node 1000 to communicate withexternal networks, computers, databases, and the like for purposes ofoperations, administration, and maintenance of the network node 1000 orother network equipment operably connected thereto.

FIG. 11 illustrates example components of a device 1100 in accordancewith some embodiments. In some embodiments, the device 1100 may includeapplication circuitry 1102, baseband circuitry 1104, Radio Frequency(RF) circuitry (shown as RF circuitry 1120), front-end module (FEM)circuitry (shown as FEM circuitry 1130), one or more antennas 1132, andpower management circuitry (PMC) (shown as PMC 1134) coupled together atleast as shown. The components of the illustrated device 1100 may beincluded in a UE or a RAN node. In some embodiments, the device 1100 mayinclude fewer elements (e.g., a RAN node may not utilize applicationcircuitry 1102, and instead include a processor/controller to process IPdata received from an EPC). In some embodiments, the device 1100 mayinclude additional elements such as, for example, memory/storage,display, camera, sensor, or input/output (I/O) interface. In otherembodiments, the components described below may be included in more thanone device (e.g., said circuitries may be separately included in morethan one device for Cloud-RAN (C-RAN) implementations).

The application circuitry 1102 may include one or more applicationprocessors. For example, the application circuitry 1102 may includecircuitry such as, but not limited to, one or more single-core ormulti-core processors. The processor(s) may include any combination ofgeneral-purpose processors and dedicated processors (e.g., graphicsprocessors, application processors, etc.). The processors may be coupledwith or may include memory/storage and may be configured to executeinstructions stored in the memory/storage to enable various applicationsor operating systems to run on the device 1100. In some embodiments,processors of application circuitry 1102 may process IP data packetsreceived from an EPC.

The baseband circuitry 1104 may include circuitry such as, but notlimited to, one or more single-core or multi-core processors. Thebaseband circuitry 1104 may include one or more baseband processors orcontrol logic to process baseband signals received from a receive signalpath of the RF circuitry 1120 and to generate baseband signals for atransmit signal path of the RF circuitry 1120. The baseband circuitry1104 may interface with the application circuitry 1102 for generationand processing of the baseband signals and for controlling operations ofthe RF circuitry 1120. For example, in some embodiments, the basebandcircuitry 1104 may include a third generation (3G) baseband processor(3G baseband processor 1106), a fourth generation (4G) basebandprocessor (4G baseband processor 1108), a fifth generation (5G) basebandprocessor (5G baseband processor 1110), or other baseband processor(s)1112 for other existing generations, generations in development or to bedeveloped in the future (e.g., second generation (2G), sixth generation(6G), etc.). The baseband circuitry 1104 (e.g., one or more of basebandprocessors) may handle various radio control functions that enablecommunication with one or more radio networks via the RF circuitry 1120.In other embodiments, some or all of the functionality of theillustrated baseband processors may be included in modules stored in thememory 1118 and executed via a Central Processing Unit (CPU 1114). Theradio control functions may include, but are not limited to, signalmodulation/demodulation, encoding/decoding, radio frequency shifting,etc. In some embodiments, modulation/demodulation circuitry of thebaseband circuitry 1104 may include Fast-Fourier Transform (FFT),precoding, or constellation mapping/demapping functionality. In someembodiments, encoding/decoding circuitry of the baseband circuitry 1104may include convolution, tail-biting convolution, turbo, Viterbi, or LowDensity Parity Check (LDPC) encoder/decoder functionality. Embodimentsof modulation/demodulation and encoder/decoder functionality are notlimited to these examples and may include other suitable functionalityin other embodiments.

In some embodiments, the baseband circuitry 1104 may include a digitalsignal processor (DSP), such as one or more audio DSP(s) 1116. The oneor more audio DSP(s) 1116 may include elements forcompression/decompression and echo cancellation and may include othersuitable processing elements in other embodiments. Components of thebaseband circuitry may be suitably combined in a single chip, a singlechipset, or disposed on a same circuit board in some embodiments. Insome embodiments, some or all of the constituent components of thebaseband circuitry 1104 and the application circuitry 1102 may beimplemented together such as, for example, on a system on a chip (SOC).

In some embodiments, the baseband circuitry 1104 may provide forcommunication compatible with one or more radio technologies. Forexample, in some embodiments, the baseband circuitry 1104 may supportcommunication with an evolved universal terrestrial radio access network(EUTRAN) or other wireless metropolitan area networks (WMAN), a wirelesslocal area network (WLAN), or a wireless personal area network (WPAN).Embodiments in which the baseband circuitry 1104 is configured tosupport radio communications of more than one wireless protocol may bereferred to as multi-mode baseband circuitry.

The RF circuitry 1120 may enable communication with wireless networksusing modulated electromagnetic radiation through a non-solid medium. Invarious embodiments, the RF circuitry 1120 may include switches,filters, amplifiers, etc. to facilitate the communication with thewireless network. The RF circuitry 1120 may include a receive signalpath which may include circuitry to down-convert RF signals receivedfrom the FEM circuitry 1130 and provide baseband signals to the basebandcircuitry 1104. The RF circuitry 1120 may also include a transmit signalpath which may include circuitry to up-convert baseband signals providedby the baseband circuitry 1104 and provide RF output signals to the FEMcircuitry 1130 for transmission.

In some embodiments, the receive signal path of the RF circuitry 1120may include mixer circuitry 1122, amplifier circuitry 1124 and filtercircuitry 1126. In some embodiments, the transmit signal path of the RFcircuitry 1120 may include filter circuitry 1126 and mixer circuitry1122. The RF circuitry 1120 may also include synthesizer circuitry 1128for synthesizing a frequency for use by the mixer circuitry 1122 of thereceive signal path and the transmit signal path. In some embodiments,the mixer circuitry 1122 of the receive signal path may be configured todown-convert RF signals received from the FEM circuitry 1130 based onthe synthesized frequency provided by synthesizer circuitry 1128. Theamplifier circuitry 1124 may be configured to amplify the down-convertedsignals and the filter circuitry 1126 may be a low-pass filter (LPF) orband-pass filter (BPF) configured to remove unwanted signals from thedown-converted signals to generate output baseband signals. Outputbaseband signals may be provided to the baseband circuitry 1104 forfurther processing. In some embodiments, the output baseband signals maybe zero-frequency baseband signals, although this is not a requirement.In some embodiments, the mixer circuitry 1122 of the receive signal pathmay comprise passive mixers, although the scope of the embodiments isnot limited in this respect.

In some embodiments, the mixer circuitry 1122 of the transmit signalpath may be configured to up-convert input baseband signals based on thesynthesized frequency provided by the synthesizer circuitry 1128 togenerate RF output signals for the FEM circuitry 1130. The basebandsignals may be provided by the baseband circuitry 1104 and may befiltered by the filter circuitry 1126.

In some embodiments, the mixer circuitry 1122 of the receive signal pathand the mixer circuitry 1122 of the transmit signal path may include twoor more mixers and may be arranged for quadrature downconversion andupconversion, respectively. In some embodiments, the mixer circuitry1122 of the receive signal path and the mixer circuitry 1122 of thetransmit signal path may include two or more mixers and may be arrangedfor image rejection (e.g., Hartley image rejection). In someembodiments, the mixer circuitry 1122 of the receive signal path and themixer circuitry 1122 may be arranged for direct downconversion anddirect upconversion, respectively. In some embodiments, the mixercircuitry 1122 of the receive signal path and the mixer circuitry 1122of the transmit signal path may be configured for super-heterodyneoperation.

In some embodiments, the output baseband signals and the input basebandsignals may be analog baseband signals, although the scope of theembodiments is not limited in this respect. In some alternateembodiments, the output baseband signals and the input baseband signalsmay be digital baseband signals. In these alternate embodiments, the RFcircuitry 1120 may include analog-to-digital converter (ADC) anddigital-to-analog converter (DAC) circuitry and the baseband circuitry1104 may include a digital baseband interface to communicate with the RFcircuitry 1120.

In some dual-mode embodiments, a separate radio IC circuitry may beprovided for processing signals for each spectrum, although the scope ofthe embodiments is not limited in this respect.

In some embodiments, the synthesizer circuitry 1128 may be afractional-N synthesizer or a fractional N/N+1 synthesizer, although thescope of the embodiments is not limited in this respect as other typesof frequency synthesizers may be suitable. For example, synthesizercircuitry 1128 may be a delta-sigma synthesizer, a frequency multiplier,or a synthesizer comprising a phase-locked loop with a frequencydivider.

The synthesizer circuitry 1128 may be configured to synthesize an outputfrequency for use by the mixer circuitry 1122 of the RF circuitry 1120based on a frequency input and a divider control input. In someembodiments, the synthesizer circuitry 1128 may be a fractional N/N+1synthesizer.

In some embodiments, frequency input may be provided by a voltagecontrolled oscillator (VCO), although that is not a requirement. Dividercontrol input may be provided by either the baseband circuitry 1104 orthe application circuitry 1102 (such as an applications processor)depending on the desired output frequency. In some embodiments, adivider control input (e.g., N) may be determined from a look-up tablebased on a channel indicated by the application circuitry 1102.

Synthesizer circuitry 1128 of the RF circuitry 1120 may include adivider, a delay-locked loop (DLL), a multiplexer and a phaseaccumulator. In some embodiments, the divider may be a dual modulusdivider (DMD) and the phase accumulator may be a digital phaseaccumulator (DPA). In some embodiments, the DMD may be configured todivide the input signal by either N or N+1 (e.g., based on a carry out)to provide a fractional division ratio. In some example embodiments, theDLL may include a set of cascaded, tunable, delay elements, a phasedetector, a charge pump and a D-type flip-flop. In these embodiments,the delay elements may be configured to break a VCO period up into Ndequal packets of phase, where Nd is the number of delay elements in thedelay line. In this way, the DLL provides negative feedback to helpensure that the total delay through the delay line is one VCO cycle.

In some embodiments, the synthesizer circuitry 1128 may be configured togenerate a carrier frequency as the output frequency, while in otherembodiments, the output frequency may be a multiple of the carrierfrequency (e.g., twice the carrier frequency, four times the carrierfrequency) and used in conjunction with quadrature generator and dividercircuitry to generate multiple signals at the carrier frequency withmultiple different phases with respect to each other. In someembodiments, the output frequency may be a LO frequency (fLO). In someembodiments, the RF circuitry 1120 may include an IQ/polar converter.

The FEM circuitry 1130 may include a receive signal path which mayinclude circuitry configured to operate on RF signals received from oneor more antennas 1132, amplify the received signals and provide theamplified versions of the received signals to the RF circuitry 1120 forfurther processing. The FEM circuitry 1130 may also include a transmitsignal path which may include circuitry configured to amplify signalsfor transmission provided by the RF circuitry 1120 for transmission byone or more of the one or more antennas 1132. In various embodiments,the amplification through the transmit or receive signal paths may bedone solely in the RF circuitry 1120, solely in the FEM circuitry 1130,or in both the RF circuitry 1120 and the FEM circuitry 1130.

In some embodiments, the FEM circuitry 1130 may include a TX/RX switchto switch between transmit mode and receive mode operation. The FEMcircuitry 1130 may include a receive signal path and a transmit signalpath. The receive signal path of the FEM circuitry 1130 may include anLNA to amplify received RF signals and provide the amplified received RFsignals as an output (e.g., to the RF circuitry 1120). The transmitsignal path of the FEM circuitry 1130 may include a power amplifier (PA)to amplify input RF signals (e.g., provided by the RF circuitry 1120),and one or more filters to generate RF signals for subsequenttransmission (e.g., by one or more of the one or more antennas 1132).

In some embodiments, the PMC 1134 may manage power provided to thebaseband circuitry 1104. In particular, the PMC 1134 may controlpower-source selection, voltage scaling, battery charging, or DC-to-DCconversion. The PMC 1134 may often be included when the device 1100 iscapable of being powered by a battery, for example, when the device 1100is included in a UE. The PMC 1134 may increase the power conversionefficiency while providing desirable implementation size and heatdissipation characteristics.

FIG. 11 shows the PMC 1134 coupled only with the baseband circuitry1104. However, in other embodiments, the PMC 1134 may be additionally oralternatively coupled with, and perform similar power managementoperations for, other components such as, but not limited to, theapplication circuitry 1102, the RF circuitry 1120, or the FEM circuitry1130.

In some embodiments, the PMC 1134 may control, or otherwise be part of,various power saving mechanisms of the device 1100. For example, if thedevice 1100 is in an RRC_Connected state, where it is still connected tothe RAN node as it expects to receive traffic shortly, then it may entera state known as Discontinuous Reception Mode (DRX) after a period ofinactivity. During this state, the device 1100 may power down for briefintervals of time and thus save power.

If there is no data traffic activity for an extended period of time,then the device 1100 may transition off to an RRC Idle state, where itdisconnects from the network and does not perform operations such aschannel quality feedback, handover, etc. The device 1100 goes into avery low power state and it performs paging where again it periodicallywakes up to listen to the network and then powers down again. The device1100 may not receive data in this state, and in order to receive data,it transitions back to an RRC_Connected state.

An additional power saving mode may allow a device to be unavailable tothe network for periods longer than a paging interval (ranging fromseconds to a few hours). During this time, the device is totallyunreachable to the network and may power down completely. Any data sentduring this time incurs a large delay and it is assumed the delay isacceptable.

Processors of the application circuitry 1102 and processors of thebaseband circuitry 1104 may be used to execute elements of one or moreinstances of a protocol stack. For example, processors of the basebandcircuitry 1104, alone or in combination, may be used to execute Layer 3,Layer 2, or Layer 1 functionality, while processors of the applicationcircuitry 1102 may utilize data (e.g., packet data) received from theselayers and further execute Layer 4 functionality (e.g., transmissioncommunication protocol (TCP) and user datagram protocol (UDP) layers).As referred to herein, Layer 3 may comprise a radio resource control(RRC) layer, described in further detail below. As referred to herein,Layer 2 may comprise a medium access control (MAC) layer, a radio linkcontrol (RLC) layer, and a packet data convergence protocol (PDCP)layer, described in further detail below. As referred to herein, Layer 1may comprise a physical (PHY) layer of a UE/RAN node, described infurther detail below.

FIG. 12 illustrates example interfaces 1200 of baseband circuitry inaccordance with some embodiments. As discussed above, the basebandcircuitry 1104 of FIG. 11 may comprise 3G baseband processor 1106, 4Gbaseband processor 1108, 5G baseband processor 1110, other basebandprocessor(s) 1112, CPU 1114, and a memory 1118 utilized by saidprocessors. As illustrated, each of the processors may include arespective memory interface 1202 to send/receive data to/from the memory1118.

The baseband circuitry 1104 may further include one or more interfacesto communicatively couple to other circuitries/devices, such as a memoryinterface 1204 (e.g., an interface to send/receive data to/from memoryexternal to the baseband circuitry 1104), an application circuitryinterface 1206 (e.g., an interface to send/receive data to/from theapplication circuitry 1102 of FIG. 11), an RF circuitry interface 1208(e.g., an interface to send/receive data to/from RF circuitry 1120 ofFIG. 11), a wireless hardware connectivity interface 1210 (e.g., aninterface to send/receive data to/from Near Field Communication (NFC)components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi®components, and other communication components), and a power managementinterface 1212 (e.g., an interface to send/receive power or controlsignals to/from the PMC 1134.

FIG. 13 is a block diagram illustrating components 1300, according tosome example embodiments, able to read instructions from amachine-readable or computer-readable medium (e.g., a non-transitorymachine-readable storage medium) and perform any one or more of themethodologies discussed herein. Specifically, FIG. 13 shows adiagrammatic representation of hardware resources 1302 including one ormore processors 1312 (or processor cores), one or more memory/storagedevices 1318, and one or more communication resources 1320, each ofwhich may be communicatively coupled via a bus 1322. For embodimentswhere node virtualization (e.g., NFV) is utilized, a hypervisor 1304 maybe executed to provide an execution environment for one or more networkslices/sub-slices to utilize the hardware resources 1302.

The processors 1312 (e.g., a central processing unit (CPU), a reducedinstruction set computing (RISC) processor, a complex instruction setcomputing (CISC) processor, a graphics processing unit (GPU), a digitalsignal processor (DSP) such as a baseband processor, an applicationspecific integrated circuit (ASIC), a radio-frequency integrated circuit(RFIC), another processor, or any suitable combination thereof) mayinclude, for example, a processor 1314 and a processor 1316.

The memory/storage devices 1318 may include main memory, disk storage,or any suitable combination thereof. The memory/storage devices 1318 mayinclude, but are not limited to any type of volatile or non-volatilememory such as dynamic random access memory (DRAM), static random-accessmemory (SRAM), erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), Flashmemory, solid-state storage, etc.

The communication resources 1320 may include interconnection or networkinterface components or other suitable devices to communicate with oneor more peripheral devices 1306 or one or more databases 1308 via anetwork 1310. For example, the communication resources 1320 may includewired communication components (e.g., for coupling via a UniversalSerial Bus (USB)), cellular communication components, NFC components,Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components,and other communication components.

Instructions 1324 may comprise software, a program, an application, anapplet, an app, or other executable code for causing at least any of theprocessors 1312 to perform any one or more of the methodologiesdiscussed herein. The instructions 1324 may reside, completely orpartially, within at least one of the processors 1312 (e.g., within theprocessor's cache memory), the memory/storage devices 1318, or anysuitable combination thereof. Furthermore, any portion of theinstructions 1324 may be transferred to the hardware resources 1302 fromany combination of the peripheral devices 1306 or the databases 1308.Accordingly, the memory of the processors 1312, the memory/storagedevices 1318, the peripheral devices 1306, and the databases 1308 areexamples of computer-readable and machine-readable media.

For one or more embodiments, at least one of the components set forth inone or more of the preceding figures may be configured to perform one ormore operations, techniques, processes, and/or methods as set forth inthe Example Section below. For example, the baseband circuitry asdescribed above in connection with one or more of the preceding figuresmay be configured to operate in accordance with one or more of theexamples set forth below. For another example, circuitry associated witha UE, base station, network element, etc. as described above inconnection with one or more of the preceding figures may be configuredto operate in accordance with one or more of the examples set forthbelow in the example section.

EXAMPLE SECTION

The following examples pertain to further embodiments.

Example 1 is a method of a g Node B (gNB) for beam searching latencyreduction, comprising: determining that a first Synchronization SignalBlock (SSB) and a second SSB are to be spatially correlated according toa spatial correlation configuration; selecting a first transmit (Tx)beam to transmit the first SSB and a second Tx beam to transmit thesecond SSB according to the spatial correlation configuration; andtransmitting the first SSB with the first Tx beam and the second SSBwith the second Tx beam.

Example 2 is the method of Example 1, wherein the spatial correlationconfiguration is based on a predefined SSB correlation pattern.

Example 3 is the method of Example 1, wherein the spatial correlationconfiguration causes the transmission of the first SSB to be in the sameslot as the transmission of the second SSB.

Example 4 is the method of Example 1, further comprising transmitting,by the gNB, a correlation message for a user equipment (UE), thecorrelation message comprising spatial correlation information toindicate to the UE that the first SSB and the second SSB are spatiallycorrelated.

Example 5 is the method of Example 4, wherein the spatial correlationinformation comprises a number of groups of SSBs that are spatiallycorrelated.

Example 6 is the method of Example 4, wherein the spatial correlationinformation comprises: a list of SSBs; and for at least one SSB in thelist, an identification of one or more other SSBs to which the at leastone SSB is spatially correlated.

Example 7 is the method of Example 4, wherein the spatial correlationinformation indicates which of a plurality of predefined SSB correlationpatterns is to be used by the gNB.

Example 8 is the method of Example 1, further comprising: preparing afirst channel-state information reference signal (CSI-RS) to be sent toa user equipment (UE), wherein the first CSI-RS is quasi co-located(QCLed) with the first SSB.

Example 9 is the method of Example 8, wherein the first CSI-RS is to besent to the UE at a same time that a second CSI-RS is to be sent to theUE.

Example 10 is a method of a user equipment (UE) for beam searchinglatency reduction, comprising: determining that first SynchronizationSignal Block (SSB) resources and second SSB resources are spatiallycorrelated; measuring the first SSB resources with a first subset ofreceive (Rx) beams of a plurality of Rx beams; measuring the second SSBresources with a second subset of Rx beams of the plurality of Rx beams;and selecting an Rx beam for both the first SSB resources and the secondSSB resources based on the measurements of the first subset of theplurality of Rx beams and the second subset of the plurality of Rxbeams.

Example 11 is the method of Example 10, wherein the UE determines thatthe first SSB resources and the second SSB resources are spatiallycorrelated based on a pre-defined SSB resource correlation pattern.

Example 12 is the method of Example 10, wherein the UE determines thatthe first SSB resources and the second SSB resources are spatiallycorrelated based on a determination that the first SSB resources and thesecond SSB resources are in a same subframe.

Example 13 is the method of Example 10, further comprising: receiving acorrelation message from a g Node B (gNB), the correlation messagecomprising spatial correlation information corresponding to the firstSSB resources and the second SSB resources; wherein the UE determinesthat the first SSB resources and the second SSB resources are spatiallycorrelated based on the spatial correlation information.

Example 14 is the method of Example 13, wherein the spatial correlationinformation comprises a number of groups of SSB resources that arespatially correlated.

Example 15 is the method of Example 13, wherein the spatial correlationinformation comprises: a list of SSB resources; and for at least one SSBresource in the list, an identification of one or more other SSBresources to which the at least one SSB resource is spatiallycorrelated.

Example 16 is the method of Example 13, wherein the spatial correlationinformation indicates which of a plurality of predefined SSB resourcecorrelation patterns is to be used by the gNB.

Example 17 is a method of a user equipment (UE) for beam latencyreduction, comprising: determining that a first SSB and a second SSB arespatially correlated; determining that a first CSI-RS is quasico-located (QCLed) with the first SSB; measuring the first CSI-RS on afirst receive (Rx) beam; and selecting the first Rx beam for use withthe second SSB based on the measurement of the first CSI-RS on the firstRx beam.

Example 18 is the method of Example 17, further comprising: determiningthat a second CSI-RS is QCLed with the second SSB; measuring the secondCSI-RS on a second Rx beam; and selecting the second Rx beam for usewith the first SSB based on the measurement of the second CSI-RS on thesecond Rx beam.

Example 19 is the method of Example 17, further comprising: determiningthat a second CSI-RS is QCLed with the second SSB; and determining thatthe first CSI-RS and the second CSI-RS are spatially correlated.

Example 20 is the method of Example 17, wherein the first CSI-RS isreceived at the UE at a same time as a second CSI-RS is received at theUE.

Example 21 is a method of a g Node B (gNB) for beam latency reduction,comprising: determining that a first Synchronization Signal Block (SSB)to be sent from an assistant transmission reception point (TRP) to auser equipment (UE) and a second SSB to be sent from the assistant TRPto the UE are to be transmitted by the assistant TRP according to aspatial correlation; and transmitting a correlation message to the UE,the correlation message comprising spatial correlation information to beused by the UE to determine that the first SSB and the second SSB asreceived from the assistant TRP are spatially correlated.

Example 22 is the method of Example 21, wherein the spatial correlationinformation comprises a number of groups of SSBs that are spatiallycorrelated.

Example 23 is the method of Example 21, wherein the spatial correlationinformation comprises: a list of SSBs; and for at least one SSB in thelist, an identification of one or more other SSBs to which the at leastone SSB is spatially correlated.

Example 24 is the method of Example 21, wherein the spatial correlationinformation indicates which of a plurality of predefined SSB correlationpatterns is to be used by the assistant TRP.

Example 25 is the method of Example 21, wherein the correlation messagefurther comprises one or more of: an actually transmitted SSB patternused by the assistant TRP; a transmission power of one or more SSBs fromthe assistant TRP; a relative transmission power of one or more SSBsfrom the assistant TRP; and a physical cell ID of the assistant TRP.

Example 26 is method of a user equipment (UE) for beam latencyreduction, comprising: receiving a correlation message from a g Node B(gNB), the correlation message comprising spatial correlationinformation indicating that a first Synchronization Signal Block (SSB)transmitted by an assistant Transmission Reception Point (TRP) and asecond SSB transmitted by the assistant TRP are spatially correlated;determining that the first SSB and the second SSB are spatiallycorrelated based on the spatial correlation information; measuring thefirst SSB with a first subset of receive (Rx) beams of a plurality of Rxbeams; measuring the second SSB with a second subset of Rx beams of theplurality of Rx beams; and selecting an Rx beam for both the first SSBand the second SSB based on the measurements of the first subset of theplurality of Rx beams and the second subset of the plurality of Rxbeams.

Example 27 is the method of Example 26, wherein the spatial correlationinformation comprises a number of groups of SSBs that are spatiallycorrelated.

Example 28 is the method of Example 26, wherein the spatial correlationinformation comprises: a list of SSBs; and for at least one SSB in thelist, an identification of one or more other SSBs to which the at leastone SSB is spatially correlated.

Example 29 is the method of Example 26, wherein the spatial correlationinformation indicates which of a plurality of predefined SSB correlationpatterns is to be used by the assistant TRP.

Example 30 is the method of Example 26, wherein the correlation messagefurther comprises one or more of: an actually transmitted SSB patternused by the assistant TRP; a transmission power of one or more SSBs fromthe assistant TRP; a relative transmission power of one or more SSBsfrom the assistant TRP; and a physical cell ID of the assistant TRP.

Example 31 may include an apparatus comprising means to perform one ormore elements of a method described in or related to any of the aboveExamples, or any other method or process described herein.

Example 32 may include one or more non-transitory computer-readablemedia comprising instructions to cause an electronic device, uponexecution of the instructions by one or more processors of theelectronic device, to perform one or more elements of a method describedin or related to any of the above Examples, or any other method orprocess described herein.

Example 33 may include an apparatus comprising logic, modules, orcircuitry to perform one or more elements of a method described in orrelated to any of the above Examples, or any other method or processdescribed herein.

Example 34 may include a method, technique, or process as described inor related to any of the above Examples, or portions or parts thereof.

Example 35 may include an apparatus comprising: one or more processorsand one or more computer-readable media comprising instructions that,when executed by the one or more processors, cause the one or moreprocessors to perform the method, techniques, or process as described inor related to any of the above Examples, or portions thereof.

Example 36 may include a signal as described in or related to any of theabove Examples, or portions or parts thereof.

Example 37 may include a datagram, packet, frame, segment, protocol dataunit (PDU), or message as described in or related to any of the aboveExamples, or portions or parts thereof, or otherwise described in thepresent disclosure.

Example 38 may include a signal encoded with data as described in orrelated to any of the above Examples, or portions or parts thereof, orotherwise described in the present disclosure.

Example 39 may include a signal encoded with a datagram, packet, frame,segment, PDU, or message as described in or related to any of the aboveExamples, or portions or parts thereof, or otherwise described in thepresent disclosure.

Example 40 may include an electromagnetic signal carryingcomputer-readable instructions, wherein execution of thecomputer-readable instructions by one or more processors is to cause theone or more processors to perform the method, techniques, or process asdescribed in or related to any of the above Examples, or portionsthereof.

Example 41 may include a computer program comprising instructions,wherein execution of the program by a processing element is to cause theprocessing element to carry out the method, techniques, or process asdescribed in or related to any of the above Examples, or portionsthereof.

Example 42 may include a signal in a wireless network as shown anddescribed herein.

Example 43 may include a method of communicating in a wireless networkas shown and described herein.

Example 44 may include a system for providing wireless communication asshown and described herein.

Example 45 may include a device for providing wireless communication asshown and described herein.

Any of the above described examples may be combined with any otherexample (or combination of examples), unless explicitly statedotherwise. The foregoing description of one or more implementationsprovides illustration and description, but is not intended to beexhaustive or to limit the scope of embodiments to the precise formdisclosed. Modifications and variations are possible in light of theabove teachings or may be acquired from practice of various embodiments.

Embodiments and implementations of the systems and methods describedherein may include various operations, which may be embodied inmachine-executable instructions to be executed by a computer system. Acomputer system may include one or more general-purpose orspecial-purpose computers (or other electronic devices). The computersystem may include hardware components that include specific logic forperforming the operations or may include a combination of hardware,software, and/or firmware.

It should be recognized that the systems described herein includedescriptions of specific embodiments. These embodiments can be combinedinto single systems, partially combined into other systems, split intomultiple systems or divided or combined in other ways. In addition, itis contemplated that parameters, attributes, aspects, etc. of oneembodiment can be used in another embodiment. The parameters,attributes, aspects, etc. are merely described in one or moreembodiments for clarity, and it is recognized that the parameters,attributes, aspects, etc. can be combined with or substituted forparameters, attributes, aspects, etc. of another embodiment unlessspecifically disclaimed herein.

It is well understood that the use of personally identifiableinformation should follow privacy policies and practices that aregenerally recognized as meeting or exceeding industry or governmentalrequirements for maintaining the privacy of users. In particular,personally identifiable information data should be managed and handledso as to minimize risks of unintentional or unauthorized access or use,and the nature of authorized use should be clearly indicated to users.

Although the foregoing has been described in some detail for purposes ofclarity, it will be apparent that certain changes and modifications maybe made without departing from the principles thereof. It should benoted that there are many alternative ways of implementing both theprocesses and apparatuses described herein. Accordingly, the presentembodiments are to be considered illustrative and not restrictive, andthe description is not to be limited to the details given herein, butmay be modified within the scope and equivalents of the appended claims.

1. A method of a g Node B (gNB) for beam searching latency reduction,comprising: determining that a first Synchronization Signal Block (SSB)and a second SSB are to be spatially correlated according to a spatialcorrelation configuration; selecting a first transmit (Tx) beam totransmit the first SSB and a second Tx beam to transmit the second SSBaccording to the spatial correlation configuration; and transmitting thefirst SSB with the first Tx beam and the second SSB with the second Txbeam.
 2. The method of claim 1, wherein the spatial correlationconfiguration is based on a predefined SSB correlation pattern.
 3. Themethod of claim 1, wherein the spatial correlation configuration causesthe transmission of the first SSB to be in the same slot as thetransmission of the second SSB.
 4. The method of claim 1, furthercomprising transmitting, by the gNB, a correlation message for a userequipment (UE), the correlation message comprising spatial correlationinformation to indicate to the UE that the first SSB and the second SSBare spatially correlated.
 5. The method of claim 4, wherein the spatialcorrelation information comprises a number of groups of SSBs that arespatially correlated.
 6. The method of claim 4, wherein the spatialcorrelation information comprises: a list of SSBs; and for at least oneSSB in the list, an identification of one or more other SSBs to whichthe at least one SSB is spatially correlated.
 7. The method of claim 4,wherein the spatial correlation information indicates which of aplurality of predefined SSB correlation patterns is to be used by thegNB.
 8. The method of claim 1, further comprising: preparing a firstchannel-state information reference signal (CSI-RS) to be sent to a userequipment (UE), wherein the first CSI-RS is quasi co-located (QCLed)with the first SSB.
 9. The method of claim 8, wherein the first CSI-RSis to be sent to the UE at a same time that a second CSI-RS is to besent to the UE.
 10. A method of a user equipment (UE) for beam searchinglatency reduction, comprising: determining that first SynchronizationSignal Block (SSB) resources and second SSB resources are spatiallycorrelated; measuring the first SSB resources with a first subset ofreceive (Rx) beams of a plurality of Rx beams; measuring the second SSBresources with a second subset of Rx beams of the plurality of Rx beams;and selecting an Rx beam for both the first SSB resources and the secondSSB resources based on the measurements of the first subset of theplurality of Rx beams and the second subset of the plurality of Rxbeams.
 11. The method of claim 10, wherein the UE determines that thefirst SSB resources and the second SSB resources are spatiallycorrelated based on a pre-defined SSB resource correlation pattern. 12.The method of claim 10, wherein the UE determines that the first SSBresources and the second SSB resources are spatially correlated based ona determination that the first SSB resources and the second SSBresources are in a same subframe.
 13. The method of claim 10, furthercomprising: receiving a correlation message from a g Node B (gNB), thecorrelation message comprising spatial correlation informationcorresponding to the first SSB resources and the second SSB resources;wherein the UE determines that the first SSB resources and the secondSSB resources are spatially correlated based on the spatial correlationinformation.
 14. The method of claim 13, wherein the spatial correlationinformation comprises a number of groups of SSB resources that arespatially correlated.
 15. The method of claim 13, wherein the spatialcorrelation information comprises: a list of SSB resources; and for atleast one SSB resource in the list, an identification of one or moreother SSB resources to which the at least one SSB resource is spatiallycorrelated.
 16. The method of claim 13, wherein the spatial correlationinformation indicates which of a plurality of predefined SSB resourcecorrelation patterns is to be used by the gNB.
 17. A method of a userequipment (UE) for beam latency reduction, comprising: determining thata first SSB and a second SSB are spatially correlated; determining thata first CSI-RS is quasi co-located (QCLed) with the first SSB; measuringthe first CSI-RS on a first receive (Rx) beam; and selecting the firstRx beam for use with the second SSB based on the measurement of thefirst CSI-RS on the first Rx beam.
 18. The method of claim 17, furthercomprising: determining that a second CSI-RS is QCLed with the secondSSB; measuring the second CSI-RS on a second Rx beam; and selecting thesecond Rx beam for use with the first SSB based on the measurement ofthe second CSI-RS on the second Rx beam.
 19. The method of claim 17,further comprising: determining that a second CSI-RS is QCLed with thesecond SSB; and determining that the first CSI-RS and the second CSI-RSare spatially correlated.
 20. The method of claim 17, wherein the firstCSI-RS is received at the UE at a same time as a second CSI-RS isreceived at the UE. 21-30. (canceled)